The present invention broadly relates to a filter for an air conditioner and heating system and more specifically to a combined mechanical particle filter and purifier element.
Three important considerations in providing for indoor air quality are airborne particles, gas phase pollutants and airborne microbes. Mechanical filtration is conventionally used to remove particles from the air. Ultraviolet photocatalytic oxidation (UVPCO) purification can remove gas phase pollutants, such as formaldehyde, and also function to destroy a large fraction of airborne microbes. Providing a system which is designed to address all of these three airborne problems presents a challenge in the field with respect to the size, complexity and cost associated with both the filtration and purification functions. It therefore can be seen that there is a need in the field of residential heating and cooling, for a system which can remove both particles from the air and effectively provide for the removal of gas phase pollutants and airborne microbes while meeting the objectives of reduced sized and low cost.
It is therefore an object of the present invention to provide a filter system which overcomes the problems of the prior art described above.
It is a further object of the present invention to provide a combination of a mechanical filtration system with ultraviolet photocatalytic air purification which can be used in a residential heating and air conditioning system.
It is a further object of the present invention to provide a combination of mechanical filtration and purification which effectively removes solid particles, gas phase pollutants and airborne microbes from an air stream.
The present invention is directed to a combination of a filter media and purification system which effectively removes solid particles, gas phase pollutants and airborne microbes by combining the mechanical filtration and ultraviolet photocatalytic oxidation functions into a single member which is positioned in a predetermined location in a residential heating and air conditioning system. More specifically the device employs a mechanical filter media that is coated with or contains a titania (titanium dioxide TiO2) component. The mechanical filtration portion of the device effectively filters solid particles from the air. The source of UV radiation is associated and placed adjacent the filter purification member. Ultraviolet light promotes ultraviolet photocatalytic oxidation (UVPCO) purification which effectively removes gas phase pollutants and airborne microbes. The coarseness and nature of the filter can be adjusted to balance the mechanical filtration efficiency with the desired pressure drop characteristic. The characteristic of the filter can also be adjusted to optimize the loading of the titania catalytic. Once exposed to ultraviolet light the filter through the titania acts as a catalyst for UVPCO. Once the filter has trapped a recommended amount of particles, it can either be washed or disposed of depending on the filter cost and material, and the type of system in which it is employed.